Catalyst for conversion of hydrocarbons, process of making and process of using thereof—bimetallic deposition

ABSTRACT

This invention is for a catalyst for conversion of hydrocarbons. The catalyst is a germanium zeolite, such as Ge-ZSM-5, on which at least two metals, platinum and at least one other metal selected from Group 7, Group 8, Group 9, Group 10 and tin, are deposited on the germanium zeolite. Examples of the other metal are iridium, rhenium, palladium, ruthenium, rhodium, iron, cobalt and tin. The catalyst is prepared by synthesizing a germanium zeolite; depositing platinum and at least one other metal on the germanium zeolite; and calcining after preparation of the zeolite, before depositing the metals or after depositing the metals. The catalyst may be used in a process for the conversion of hydrocarbons, such as propane to aromatics, by contacting the catalyst with a hydrocarbon stream containing alkanes, olefins and mixtures thereof having 2 to 12 carbon atoms per molecule and recovering the product.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a catalyst for hydrocarbon conversion, e.g., acatalyst for the aromatization of alkanes, olefins and mixtures thereofhaving two to twelve carbon atoms per molecule. The catalyst is amicroporous silicate, aluminosilicate, aluminophosphate orsilicoaluminophosphate on which a metal has been deposited.

2. Description of the Prior Art

Crystalline silicates, aluminosilicates, aluminophosphates andsilicoaluminophosphates are known catalysts for hydrocarbon conversionand may contain other metals. An aluminosilicate such as a zeolite mayinclude not only aluminum and silicon but other trivalent elements whichreplace aluminum and other tetravalent elements which replace silicon.Also, other elements may be deposited on the silicate, aluminosilicate,aluminophosphate or silicoaluminophosphate.

U.S. Pat. No. 4,310,440 discloses crystalline aluminophosphates having aframework structure with chemical composition in mole ratios of1Al₂O₃:1.0±0.2P₂O₅ and being microporous with uniform pores of nominaldiameters from about 3 to about 10 angstroms.

U.S. Pat. No. 4,440,871 discloses crystalline microporoussilicoaluminophosphates having pores which are uniform and have nominaldiameters of greater than about 3 angstroms with a chemical compositionof mole fractions of silicon, aluminum and phosphorus within thepentagonal composition area defined by

Mole Fraction x y z A 0.01 0.47 0.52 B 0.94 0.01 0.05 C 0.98 0.01 0.01 D0.39 0.60 0.01 E 0.01 0.60 0.39where x, y and z are the mole fractions of silicon, aluminum andphosphorus and ACBDE are points defining a pentagonal area of a ternarydiagram as shown in FIG. 1 of U.S. Pat. No. 4,440,871.

SUMMARY OF THE INVENTION

This invention provides a catalyst containing silicon, aluminum,phosphorus, as needed to form a silicate, aluminosilicate,aluminophosphate (AlPO) or silicoaluminophosphate (SAPO) with at leastone other element selected from Group 4, Group 5, Group 13, Group 14,Group 15 and the first series transition metals in a three dimensionalinterconnecting crystalline tetrahedral framework. The crystallinetetrahedral framework is synthesized from an aqueous gel containing, asneeded, a silica source, an aluminum source, a phosphorus source, asource for the Group 4, Group 5, Group 13, Group 14, Group 15 and thefirst series transition metal element(s) and, optionally, an organicstructure-directing agent. The reaction mixture is heated to formcrystals and then cooled. The crystals are separated from the synthesisliquor and are washed, dried and calcined. At least one metal selectedfrom Group 6, Group 7, Group 8, Group 9 or Group 10 is deposited on thesilicate, aluminosilicate, aluminophosphate or silicoaluminophosphate(hereinafter referred to as “deposited metal”). The catalyst may be usedin a process for converting C₂-C₁₂ hydrocarbons into aromatics.

One example of the invention is a catalyst of a germanium zeolite onwhich platinum and at least one other metal selected from Group 7, Group8, Group 9 or Group 10, such as rhenium, ruthenium, rhodium, iridium,palladium, cobalt and iron. The zeolite may be MFI (ZSM-5). This exampleof the invention includes a process for synthesizing the germaniumzeolite catalyst by: a) preparing a germanium zeolite; b) depositingplatinum and at least other metal selected from Group 7, Group 8, Group9 or Group 10 on the germanium zeolite; and c) calcining the germaniumzeolite on which platinum and the other metal has been deposited. Thisexample of the invention also includes a process for the conversion ofhydrocarbons of: a) contacting a hydrocarbon stream containing alkanesand/or olefins having 2 to 12 carbon atoms per molecule with at leastone germanium zeolite catalyst comprising platinum and at least oneother metal selected from Group 7, Group 8, Group 9 or Group 10deposited on the germanium zeolite; and b) recovering the product.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the invention and many of the attendantadvantages thereof will be readily understood by reference to thefollowing detailed description when considered in connection with theaccompanying drawings wherein:

FIG. 1 is a graph of propane conversion, BTX selectivity and fuel gasselectivity for Ir—Pt/Ge-ZSM-5 without H₂S pretreatment

FIG. 2 is a graph of propane conversion, BTX selectivity and fuel gasselectivity for Ir—Pt/Ge-ZSM-5 with H₂S pretreatment

FIG. 3 is a graph of propane conversion, BTX selectivity and fuel gasselectivity for Re—Pt/Ge-ZSM-5 without H₂S pretreatment

FIG. 4 is a graph of propane conversion, BTX selectivity and fuel gasselectivity for Re—Pt/Ge-ZSM-5 with H₂S pretreatment

FIG. 5 is a graph of propane conversion, BTX selectivity and fuel gasselectivity for Pd—Pt/Ge-ZSM-5 without H₂S pretreatment

FIG. 6 is a graph of propane conversion, BTX selectivity and fuel gasselectivity for Pd—Pt/Ge-ZSM-5 with H₂S pretreatment

FIG. 7 is a graph of propane conversion, BTX selectivity and fuel gasselectivity for Ru—Pt/Ge-ZSM-5 without H₂S pretreatment

FIG. 8 is a graph of propane conversion, BTX selectivity and fuel gasselectivity for Rh—Pt/Ge-ZSM-5 without H₂S pretreatment

FIG. 9 is a graph of propane conversion, BTX selectivity and fuel gasselectivity for Rh—Pt/Ge-ZSM-5 with H₂S pretreatment

FIG. 10 is a graph of propane conversion, BTX selectivity and fuel gasselectivity for Fe—Pt/Ge-ZSM-5 without H₂S pretreatment

FIG. 11 is a graph of propane conversion, BTX selectivity and fuel gasselectivity for Fe—Pt/Ge-ZSM-5 with H₂S pretreatment

FIG. 12 is a graph of propane conversion, BTX selectivity and fuel gasselectivity for Co—Pt/Ge-ZSM-5 (Synthesis B) without H₂S pretreatment

FIG. 13 is a graph of propane conversion, BTX selectivity and fuel gasselectivity for Co—Pt/Ge-ZSM-5 (Synthesis A) with H₂S pretreatment

FIG. 14 is a graph of propane conversion, BTX selectivity and fuel gasselectivity for Sn—Pt/Ge-ZSM-5 without H₂S pretreatment

DETAILED DESCRIPTION OF THE INVENTION

Crystalline silicates, aluminosilicates, aluminophosphates andsilicoaluminophosphates have uniform pores through which molecules candiffuse. Aluminosilicates include zeolites. Examples of zeolites are MFI(ZSM-5), BEA (Beta), MWW (MCM-22), MOR (Mordenite), LTL (Zeolite L), MTT(ZSM-23), MTW (ZSM-12), TON (ZSM-22) and MEL (ZSM-11).

Crystalline silicates, aluminosilicates, aluminophosphates andsilicoaluminophosphates have structures of TO₄ tetrahedra, which form athree dimensional network by sharing oxygen atoms where T representstetravalent elements, such as silicon, trivalent elements, such asaluminum, and pentavalent elements, such as phosphorus. “Zeolite” in thepresent application includes aluminosilicates with openthree-dimensional framework structures composed of corner-sharing TO₄tetrahedra, where T is Al or Si, but also includes tetravalent,trivalent and divalent T atoms which able to isoelectronically replaceSi and Al in the framework, e.g., germanium (4+), titanium (4+), boron(3+), gallium (3+), iron (3+), zinc (2+) and beryllium (2+). “Zeolite”is primarily a description of structure, not composition.

Silicates, aluminosilicates, aluminophosphates andsilicoaluminophosphates generally crystallize from an aqueous solution.The typical technique for synthesizing silicates, aluminosilicates,aluminophosphates or silicoaluminophosphates comprises converting anaqueous gel of a silica source, an aluminum source and a phosphorussource, as needed, to crystals by a hydrothermal process, employing adissolution/recrystallization mechanism. The reaction medium may alsocontain an organic structure-directing agent which is incorporated inthe microporous space of the crystalline network during crystallization,thus controlling the construction of the network and assisting tostabilize the structure through the interactions with the silicon,aluminum or phosphorus components.

The aqueous gel contains in addition to the silica source, the aluminumsource, the phosphorus source, as needed, and the optional organicstructure-directing agent and a source of at least one other elementfrom Group 4, Group 5, Group 13, Group 14, Group 15 or the first seriestransition metals to be incorporated into the framework of the silicate,aluminosilicate, aluminophosphate or silicoaluminophosphate.

Examples of the silica source are silicon oxide or silica (SiO₂) whichis available in various forms, such as silica sol, commerciallyavailable as Ludox AS-40™, precipitated silica, commercially availableas Ultrasil VN3SP™ and fumed silica, commercially available as Aerosil200™.

Examples of the aluminum source are sodium aluminate, aluminum nitrate,aluminum sulfate, aluminum hydroxide and pseudobohemite.

Examples of the phosphorus source are phosphoric acid (85 wt %), P₂O₅,orthophosphoric acid, triethylphosphate and sodium metaphosphate.

Examples of the source of Group 4, Group 5, Group 13, Group 14, Group 15and the first series transition metals are oxides, chlorides, sulfates,alkoxides, fluorides, nitrates and oxalates.

Examples of the structure-directing agent are organic amine andquaternary ammonium compounds and salts and cations thereof, such astetra n-propyl ammonium hydroxide, tetra n-propyl ammonium bromide andtetra n-propyl ammonium chloride, tetraethyl ammonium hydroxide,hexamethyleneimine, 1,4-di(1′4′-diazabicyclo[2.2.2]octane)butanehydroxide, morpholine, cyclohexylamine and diethylethanolamine,N,N′-diisopropyl imidazolium cation, tetrabutylammonium compounds,di-n-propylamine (DPA), tripropylamine, triethylamine (TEA),triethanolamine, piperidine, 2-methylpyridine, N,N-dimethylbenzylamine,N,N-diethylethanolamine, dicyclohexylamine, N,N-dimethylethanolamine,choline cation, N,N′-dimethylpiperazine, 1,4-diazabicyclo(2,2,2)octane,N′,N′,N,N-tetramethyl-(1,6)hexanediamine, N-methyldiethanolamine,N-methyl-ethanolamine, N-methyl piperidine, 3-methyl-piperidine,N-methylcyclohexylamine, 3-methylpyridine, 4-methyl-pyridine,quinuclidine, N,N′-dimethyl-1,4-diazabicyclo(2,2,2) octane ion;di-n-butylamine, neopentylamine, di-n-pentylamine, isopropylamine,t-butyl-amine, ethylenediamine, pyrrolidine, 2-imidazolidone, aN-benzyl-1,4-diazabicyclo[2.2.2]octane cation, a1-[1-(4-chlorophenyl)-cyclopropylmethyl]-1-ethyl-pyrrolidinium or1-ethyl-1-(1-phenyl-cyclopropylmethyl)-pyrrolidium cation and mixturesthereof.

The reaction may also utilize an acid as a reagent. The acid may be aBronsted acid or a Lewis acid. Examples without limitation of an aciduseful in the present invention are sulfuric acid, acetic acid, nitricacid, phosphoric acid, hydrochloric acid, hydrofluoric acid, oxalic acidor formic acid.

The reaction mixture is stirred and heated to a temperature of about100° C. to about 200° C. to form crystals. The reaction mixture iscooled to room temperature. The crystals are separated from thesynthesis liquor. The liquid portion of the synthesis liquor may beremoved by filtration, evaporation, spray drying or any other means forremoving liquids, e.g., water, from the crystals. The crystals arewashed with water and then dried and calcined.

The silicates are essentially aluminum-free but may contain aluminum andother impurities up to 500 ppm.

The aluminosilicates may have a silicon to aluminum atomic ratio (Si:Al)greater than 2:1. In one embodiment of the present invention, thesilicon to aluminum atomic ratio is in the range from 15:1 to 200:1. Inanother embodiment of the present invention, the silicon to aluminumatomic ratio is in the range from 18:1 to 100:1.

The aluminophosphates may have an aluminum to phosphorus atomic ratio(Al:P) in the range from about 0.8:1 to about 1.2:1 as disclosed in U.S.Pat. No. 4,310,440, hereby incorporated by reference.

The silicoaluminophosphates may have a silicon to aluminum to phosphorusatomic represented by (S_(x)Al_(y)P_(z))O₂ where “x”, “y” and “z”represent the mole fractions of silicon, aluminum and phosphorusrespectively, present as tetrahedral oxides, said mole fractions beingsuch that they are within the pentagonal compositional area defined bypoints ABCD and E of a ternary diagram with values represented in thetable below:

Mole Fraction x y z A 0.01 0.47 0.52 B 0.94 0.01 0.05 C 0.98 0.01 0.01 D0.39 0.60 0.01 E 0.01 0.60 0.39as disclosed in U.S. Pat. No. 4,440,871, hereby incorporated byreference.

The amount of Group 4, Group 5, Group 13, Group 14, Group 15 and thefirst series transition metals present in the crystalline framework isin the range from 0.1 wt. % to 25 wt. %. In one embodiment of thepresent invention, this range is from 0.1 wt. % to 10 wt. %. In anotherembodiment of the present invention, this range is from 0.1 wt. % to 5wt. %.

The silicate, aluminosilicate, aluminophosphate orsilicoaluminophosphate has average pore size in the range from 2angstroms to 20 angstroms, i.e., microporous.

At least one metal selected from Group 6, Group 7, Group 8, Group 9 orGroup 10 is deposited on the silicate, aluminosilicate, aluminophosphateor silicoaluminophosphate (“deposited metal”). The metal is depositednot only on the surface of the silicate, aluminosilicate,aluminophosphate or silicoaluminophosphate but also in the pores andchannels which occur in the silicate, aluminosilicate, aluminophosphateor silicoaluminophosphate. The metal is deposited on the silicate,aluminosilicate, aluminophosphate or silicoaluminophosphate by any knownmethod of depositing a metal on a silicate, aluminosilicate,aluminophosphate or silicoaluminophosphate. Typical methods ofdepositing a metal on a silicate, aluminosilicate, aluminophosphate orsilicoaluminophosphate are ion exchange and impregnation. In oneembodiment of the present invention, the metal is present in the rangefrom 0.05% to 3% by weight. In another embodiment of the presentinvention, the metal is present in the range from 0.1% to 2% by weight.In another embodiment of the present invention, the metal is present inthe range from 0.2 to 1.5% by weight.

However, for silicate, aluminosilicate, aluminophosphate orsilicoaluminophosphate-based catalysts on which metals have beendeposited, the process temperatures and catalyst regenerationtemperatures cause the metal to “sinter”, i.e., agglomeration of themetal particles resulting in an increase of metal particle size on thesurface of the zeolite and a decrease of metal surface area, causing aloss of catalyst performance, specifically catalyst performance, e.g.,activity and/or selectivity.

Without the present invention and its claims being limited by theory, itis believed that certain elements in the framework and certain metalsdeposited on the silicate, aluminosilicate, aluminophosphate orsilicoaluminophosphate associate to resist sintering of the depositedmetal. U.S. Pat. No. 6,784,333 discloses and claims analuminum-silicon-germanium zeolite on which platinum has been depositedfor use in a process for the aromatization of hydrocarbons. The presenceof germanium in the framework of the zeolite and the presence ofplatinum deposited on the zeolite apparently results in higherselectivity for benzene, toluene and xylenes (BTX) which remainsessentially constant over a significant time on stream. Without theinvention of U.S. Pat. No. 6,784,333 and its claims being limited bytheory, it may be that the germanium in the framework and the platinumdeposited on the zeolite associate such that the platinum remainsdispersed and sintering is reduced.

Besides germanium, there may be other elements in the crystallineframework which associate with platinum or other deposited metals.Elements in the crystalline framework may be selected from Group 4,Group 5, Group 13, Group 14, Group 15 and the first series transitionmetals of the Periodic Table of Elements. Specific examples of theseelements are germanium, boron, gallium, indium, tin, titanium,zirconium, vanadium, chromium, iron, niobium and phosphorus. One or moreelements may be in the crystalline framework.

Besides platinum, there may be other deposited metals which associatewith germanium or other elements in the crystalline framework. Depositedmetals may be selected from Group 6, Group 7, Group 8, Group 9 or Group10 of the Periodic Table of Elements. Specific examples of the depositedmetal are platinum, molybdenum, rhenium, nickel, ruthenium, rhodium,palladium, osmium and iridium. One or more metals, such as bimetallics,e.g., Pt/Sn, Pt/Ge, Pt/Pb or metal/metal oxide combinations, e.g.Pt/GeO₂, may be deposited. Specific examples of more than one metalbeing deposited are platinum and another metal selected from rhenium,ruthenium, rhodium, iridium or palladium.

The crystalline framework of which these elements from Group 4, Group 5,Group 13, Group 14, Group 15 and the first series transition metals arepart and on which metals selected from Group 6, Group 7, Group 8, Group9 or Group 10 are deposited need not be limited to a zeolite but may beany microporous silicate, aluminosilicate, aluminophosphate orsilicoaluminophosphate.

Before or after deposition of the metal, the silicate, aluminosilicate,aluminophosphate or silicoaluminophosphate may be bound by oxides orphosphates of magnesium, aluminum, titanium, zirconium, thorium,silicon, boron or mixtures thereof. The process steps of binding anddepositing metal can occur in any order. Binding may occur before orafter metal deposition.

The catalyst may be calcined at different stages in the synthesis. Thesilicate, aluminosilicate, aluminophosphate or silicoaluminophosphatemay be calcined to remove the organic structure-directing agent. Thiscalcination is at a temperature of about 300° C. to about 1000° C. orabout 300° C. to about 750° C. for a time sufficient to removeessentially all of any structure-directing agent, e.g., one to six hoursor about four hours. One example of calcination is at 550° C. for tenhours. Calcination may occur after binding. This calcination is at atemperature in the range of from about 300° C. to about 1000° C. for atime in the range of from about one hour to about 24 hours. Calcinationmay also occur after metal deposition to fix the metal. This calcinationshould not exceed a temperature of 500° C. and may be at a temperatureof about 200° C. to about 500° C. for a time in the range of from about0.5 hour to about 24 hours. These calcinations need not be separate butmay be combined to accomplish more than one purpose. When the silicate,aluminosilicate, aluminophosphate or silicoaluminophosphate is calcined,it may be bound or unbound and it may have metal deposited on it or not.Calcination can occur in an environment of oxygen, nitrogen, watervapor, helium and mixtures thereof.

The catalyst, bound or unbound, will have porosity in addition to theuniform porosity of the silicate, aluminosilicate, aluminophosphate orsilicoaluminophosphate. For an unbound catalyst, the average pore sizeof the catalyst may vary in the range from 2 angstroms to 100 angstroms.In one embodiment of the present invention, the average pore size is inthe range from 5 angstroms to 50 angstroms. In another embodiment of thepresent invention, the average pore size is in the microporous rangefrom 5 angstroms to 20 angstroms. For a bound catalyst, the average poresize of the catalyst may vary from 5 angstroms up to 100 microns.

Some catalysts used for hydrocarbon conversion are susceptible to sulfurpoisoning. However, for some catalysts used for hydrocarbon conversion,modest amounts of sulfur, such as about 0 to 200 ppm in the feed, areacceptable and sometimes preferred. The catalyst may also be pretreatedwith sulfur. A standard sulfurization method that is well known in theart consists in heating in the presence of a sulfur compound, such ashydrogen sulfide, or a mixture of a sulfur compound and an inert gas,such as hydrogen or nitrogen, to a temperature of between 150 and 800°C. Non-limiting examples of sulfur compounds are H₂S, an organosulfidecompound, such as dimethyl disulfide or DMSO (dimethyl sulfoxide), orC_(n)H₂n+₂S or C_(n)H₂n+₂S₂, where n=1-20. In one embodiment of thepresent invention, the temperature is between 250 and 600° C.

The catalyst may contain a reaction product, such as a sulfide of thedeposited metal, that is formed by contacting the catalyst with sulfuror a sulfur compound. In one embodiment of the present invention, theamount of sulfur on the catalyst is in the range of from 10 ppm to 0.1wt. %.

The catalyst may also contain elements other than sulfur, such as tin,germanium or lead. These elements would be present in the range of from1:1 to 1:100 as a ratio of the deposited metal to tin, germanium orlead. These elements may be added to the catalyst by wet impregnation,chemical vapor deposition or other methods known in the art.

The silicate, aluminosilicate, aluminophosphate orsilicoaluminophosphate-based catalyst which contains at least oneelement selected from Group 4, Group 5, Group 13, Group 14, Group 15 andthe first series transition metals isomorphously incorporated into thezeolite framework and at least one metal selected from Group 6, Group 7,Group 8, Group 9 or Group 10 deposited on the zeolite can be used in aprocess for conversion of hydrocarbon streams containing C₂-C₁₂ alkanes,olefins and mixtures thereof, said alkanes and olefins which may bestraight, branched, cyclic or mixtures thereof, into aromatics.

The zeolite may be base-exchanged with an alkali metal or alkaline earthmetal, such as cesium, potassium, sodium, rubidium, barium, calcium,magnesium and mixtures thereof, to reduce acidity and form a non-acidiczeolite. A non-acidic zeolite has substantially all of its cationicsites of exchange, e.g., those typically associated with aluminum,occupied by nonhydrogen cationic species, e.g., alkali or alkaline earthmetals. The base-exchange may occur before or after the noble metal isdeposited. Such a base-exchanged catalyst may be used to convert C₆-C₁₂alkanes, olefins and mixtures thereof, such as might be obtained fromnatural gas condensate, light naphtha, raffinate from aromaticsextraction and other refinery or chemical processes, to aromatics, suchas benzene, ethyl benzene, toluene and xylenes. Base-exchange may takeplace during synthesis of the zeolite with an alkali metal or alkalineearth metal being added as a component of the reaction mixture or maytake place with a crystalline zeolite before or after deposition of thenoble metal. The zeolite is base-exchanged to the extent that most orall of the cations associated with aluminum are alkali metal or alkalineearth metal. An example of a monovalent base:aluminum molar ratio in thezeolite after base exchange is at least about 0.9. For a divalent ortrivalent base, the molar ratio would be half (0.45) or a third (0.3) asthat for a monovalent base, respectively, and for mixtures ofmonovalent, divalent and trivalent bases, the above molar ratios wouldbe apportioned by their respective content in the mixture.

Depending on the element incorporated into the zeolite framework, thezeolite may be non-acidic within the present invention withoutbase-exchange, e.g., boron, germanium or tin in an aluminum-freezeolite. “Aluminum-free” has a meaning of having aluminum content of nomore than 0.4 wt %. Within the meaning and for the purposes of thepresent invention, a zeolite may be non-acidic by exchange with a baseor by having a low aluminum content.

Examples of hydrocarbon conversion processes for which this catalyst canbe used are:

-   (A) The catalytic cracking of a naphtha feed to produce light    olefins. Typical reaction conditions include from about 500° C. to    about 750° C., pressures of subatmospheric or atmospheric, generally    ranging up to about 10 atmospheres (gauge) and catalyst residence    time (volume of the catalyst/feed rate) from about 10 milliseconds    to about 10 seconds.-   (B) The catalytic cracking of high molecular weight hydrocarbons to    lower weight hydrocarbons. Typical reaction conditions for catalytic    cracking include temperatures of from about 400° C. to about 700°    C., pressures of from about 0.1 atmosphere (bar) to about 30    atmospheres, and weight hourly space velocities of from about 0.1 to    about 100 hr⁻¹.-   (C) The transalkylation of aromatic hydrocarbons in the presence of    polyalkylaromatic hydrocarbons. Typical reaction conditions include    a temperature of from about 200° C. to about 500° C., a pressure of    from about atmospheric to about 200 atmospheres, a weight hourly    space velocity of from about 1 to about 100 hr¹ and an aromatic    hydrocarbon/polyalkylaromatic hydrocarbon mole ratio of from about    1/1 to about 16/1.-   (D) The isomerization of aromatic (e.g., xylene) feedstock    components. Typical reaction conditions for such include a    temperature of from about 230° C. to about 510° C., a pressure of    from about 0.5 atmospheres to about 50 atmospheres, a weight hourly    space velocity of from about 0.1 to about 200 hr⁻¹ and a    hydrogen/hydrocarbon mole ratio of from about 0 to about 100.-   (E) The dewaxing of hydrocarbons by selectively removing straight    chain paraffins. The reaction conditions are dependent in large    measure on the feed used and upon the desired pour point. Typical    reaction conditions include a temperature between about 200° C. and    450° C., a pressure up to 3,000 psig and a liquid hourly space    velocity from 0.1 to 20 hr⁻¹.-   (F) The alkylation of aromatic hydrocarbons, e.g., benzene and    alkylbenzenes, in the presence of an alkylating agent, e.g.,    olefins, formaldehyde, alkyl halides and alcohols having 1 to about    20 carbon atoms. Typical reaction conditions include a temperature    of from about 100° C. to about 500° C., a pressure of from about    atmospheric to about 200 atmospheres, a weight hourly space velocity    of from about 1 hr⁻¹ to about 100 hr⁻¹ and an aromatic    hydrocarbon/alkylating agent mole ratio of from about 1/11 to about    20/1.-   (G) The alkylation of aromatic hydrocarbons, e.g., benzene, with    long chain olefins, e.g., C₁₄ olefin. Typical reaction conditions    include a temperature of from about 50° C. to about 200° C., a    pressure of from about atmospheric to about 200 atmospheres, a    weight hourly space velocity of from about 2 hr⁻¹ to about 2000 hr⁻¹    and an aromatic hydrocarbon/olefin mole ratio of from about 1/1 to    about 20/1. The resulting products from the reaction are long chain    alkyl aromatics which when subsequently sulfonated have particular    application as synthetic detergents.-   (H) The alkylation of aromatic hydrocarbons with light olefins to    provide short chain alkyl aromatic compounds, e.g., the alkylation    of benzene with propylene to provide cumene. Typical reaction    conditions include a temperature of from about 10° C. to about 200°    C., a pressure of from about 1 to about 30 atmospheres, and an    aromatic hydrocarbon weight hourly space velocity (WHSV) of from 1    hr⁻¹ to about 50 hr⁻¹.-   (I) The hydrocracking of heavy petroleum feedstocks, cyclic stocks,    and other hydrocrack charge stocks. The zeolite-bound high silica    zeolite will contain an effective amount of at least one    hydrogenation component of the type employed in hydrocracking    catalysts.-   (J) The alkylation of a reformate containing substantial quantities    of benzene and toluene with fuel gas containing short chain olefins    (e.g., ethylene and propylene) to produce mono- and dialkylates.    Preferred reaction conditions include temperatures from about    100° C. to about 250° C., a pressure of from about 100 to about 800    psig, a WHSV-olefin from about 0.4 hr⁻¹ to about 0.8 hr⁻¹, a    WHSV-reformate of from about 1 hr⁻¹ to about 2 hr⁻¹ and, optionally,    a gas recycle from about 1.5 to 2.5 vol/vol fuel gas feed.-   (K) The alkylation of aromatic hydrocarbons, e.g., benzene, toluene,    xylene, and naphthalene, with long chain olefins, e.g., C₁₄ olefin,    to produce alkylated aromatic lube base stocks. Typical reaction    conditions include temperatures from about 100° C. to about 400° C.    and pressures from about 50 to 450 psig.-   (L) The alkylation of phenols with olefins or equivalent alcohols to    provide long chain alkyl phenols. Typical reaction conditions    include temperatures from about 100° C. to about 250° C., pressures    from about 1 to 300 psig and total WHSV of from about 2 hr⁻¹ to    about 10 hr⁻¹.-   (M) The conversion of light paraffins to olefins and/or aromatics.    Typical reaction conditions include temperatures from about 425° C.    to about 760° C. and pressures from about 10 to about 2000 psig.-   (N) The conversion of light olefins to gasoline, distillate and lube    range hydrocarbons. Typical reaction conditions include temperatures    of from about 175° C. to about 500° C. and a pressure of from about    10 to about 2000 psig.-   (O) Two-stage hydrocracking for upgrading hydrocarbon streams having    initial boiling points above about 200° C. to premium distillate and    gasoline boiling range products or as feed to further fuels or    chemicals processing steps. The first stage can be the zeolite-bound    high silica zeolite comprising one or more catalytically active    substances, e.g., a Group 8 metal, and the effluent from the first    stage would be reacted in a second stage using a second zeolite,    e.g., zeolite Beta, comprising one or more catalytically active    substances, e.g., a Group 8 metal, as the catalyst. Typical reaction    conditions include temperatures from about 315° C. to about 455° C.,    a pressure from about 400 to about 2500 psig, hydrogen circulation    of from about 1000 to about 10,000 SCF/bbl and a liquid hourly space    velocity (LHSV) of from about 0.1 to 10 hr⁻¹.-   (P) A combination hydrocracking/dewaxing process in the presence of    the zeolite-bound high silica zeolite comprising a hydrogenation    component and a zeolite such as zeolite Beta. Typical reaction    conditions include temperatures from about 350° C. to about 400° C.,    pressures from about 1400 to about 1500 psig, LHSV from about 0.4 to    about 0.6 hr⁻¹ and a hydrogen circulation from about 3000 to about    5000 SCF/bbl.-   (Q) The reaction of alcohols with olefins to provide mixed ethers,    e.g., the reaction of methanol with isobutene and/or isopentene to    provide methyl-t-butyl ether (MTBE) and/or t-amyl methyl ether    (TAME). Typical conversion conditions include temperatures from    about 20° C. to about 200° C., pressures from 2 to about 200 atm,    WHSV (gram of olefin per hour per gram of zeolite) from about 0.1    hr⁻¹ to about 200 hr⁻¹ and an alcohol to olefin molar feed ratio    from about 0.1/1 to about 5/1.-   (R) The disproportionation of aromatics, e.g. the disproportionation    of toluene to make benzene and xylenes. Typical reaction conditions    include a temperature of from about 200° C. to about 760° C., a    pressure of from about atmospheric to about 60 atmosphere (bar), and    a WHSV of from about 0.1 hr⁻¹ to about 30 hr⁻¹.-   (S) The conversion of naphtha (e.g., C₆-C₁₀) and similar mixtures to    highly aromatic mixtures. Thus, normal and slightly branched chained    hydrocarbons, preferably having a boiling range above about 40° C.,    and less than about 200° C., can be converted to products having a    substantially higher octane aromatics content by contacting the    hydrocarbon feed with the zeolite at a temperature in the range of    from about 400° C. to 600° C., preferably 480° C. to 550° C. at    pressures ranging from atmospheric to 40 bar, and liquid hourly    space velocities (LHSV) ranging from 0.1 to 15 hr⁻¹.-   (T) The adsorption of alkyl aromatic compounds for the purpose of    separating various isomers of the compounds.-   (U) The conversion of oxygenates, e.g., alcohols, such as methanol,    or ethers, such as dimethylether, or mixtures thereof to    hydrocarbons including olefins and aromatics with reaction    conditions including a temperature of from about 275° C. to about    600° C., a pressure of from about 0.5 atmosphere to about 50    atmospheres and a liquid hourly space velocity of from about 0.1 to    about 100.-   (V) The oligomerization of straight and branched chain olefins    having from about 2 to about 5 carbon atoms. The oligomers which are    the products of the process are medium to heavy olefins which are    useful for both fuels, i.e., gasoline or a gasoline blending stock,    and chemicals. The oligomerization process is generally carried out    by contacting the olefin feedstock in a gaseous phase with a    zeolite-bound high silica zeolite at a temperature in the range of    from about 250° C. to about 800° C., a LHSV of from about 0.2 to    about 50 and a hydrocarbon partial pressure of from about 0.1 to    about 50 atmospheres. Temperatures below about 250° C. may be used    to oligomerize the feedstock when the feedstock is in the liquid    phase when contacting the zeolite-bound high silica zeolite    catalyst. Thus, when the olefin feedstock contacts the catalyst in    the liquid phase, temperatures of from about 10° C. to about 250° C.    can be used.-   (W) The conversion of C₂ unsaturated hydrocarbons (ethylene and/or    acetylene) to aliphatic C₆₋₁₂ aldehydes and converting said    aldehydes to the corresponding C₆₋₁₂ alcohols, acids, or esters.-   (X) The desulfurization of FCC (fluid catalytic cracking) feed    streams. The desulfurization process is generally carried out at a    temperature ranging from 100° C. to about 600° C., preferably from    about 200° C. to about 500° C., and more preferably from about    260° C. to about 400° C., at a pressure ranging from 0 to about 2000    psig, preferably from about 60 to about 1000 psig, and more    preferably from about 60 to about 500 psig, at a LHSV ranging from 1    to 10 h⁻¹. The hydrocarbon mixtures which can be desulfurized    according to the process of the present invention contain more than    150 ppm of sulfur, e.g., hydrocarbon mixtures with a sulfur content    higher than 1000 ppm, even higher than 10000 ppm.

The invention having been generally described, the following examplesare given as particular embodiments of the invention and to demonstratethe practice and advantages thereof. It is understood that the examplesare given by way of illustration and are not intended to limit thespecification or the claims to follow in any manner.

Synthesis of Ge-ZSM-5

Chemicals Used:

-   “Ludox AS-40 colloidal silica SiO₂; 40 wt. % suspension in water;    Aldrich;-   Sodium hydroxide NaOH, 50 wt. % solution in water; Sigma-Aldrich;-   Germanium dioxide GeO₂; Germanium Corporation of America GTAH 68002;-   Sodium aluminate NaAlO₂ (23.6 wt. % Al₂O₃; 19.4 wt. % Na₂O; 57.0 wt.    % H₂O); Southern Ionics;-   Tetrapropylammonium hydroxide (CH₃CH₂CH₂)₄NOH, 40 wt. % solution in    water; SACHEM;-   Acetic acid CH₃CO₂H, 99.7%; Aldrich.    Solution 1.

18.1 grams of sodium hydroxide solution was mixed with 155 grams of D.I.water. 7.4314 grams of GeO₂ were dissolved in the solution withstiffing.

Solution 2.

1.93 grams of sodium aluminate were mixed with 165 grams of D.I. water.

Solution 1 was poured into 160 grams of Ludox AS-40 with vigorous gelstirring for 40 minutes. Solution 2 was introduced into gel withstirring for 10 minutes. Tetrapropylammonium hydroxide (112.46 grams)was added to the mixture and gel was stirred for about one hour.

25.73 grams of acetic acid was added to gel with continuous stirring. pHof gel in ten minutes was 9.10.

Crystallization was made in 1 L stainless steel autoclave at 160° C.with stirring (300 rpm) for 36 hours. Zeolite was filtered and washedwith D.I. water. Zeolite was dried at 90° C. overnight and was calcinedat 550° C. for 10 hours in an oven with forced air flow.

Example 1 Synthesis of Pt—Ir/Ge-ZSM-5

Chemicals Used:

-   Ammonium hexachloroiridate(III) hydrate (NH₄)₂IrCl₆.H₂O; (% Ir    38.9%); Strem Chemicals;-   Tetraammineplatinum (II) nitrate (NH₂)₄Pt(NO₃)₂; Aldrich;-   Ethylenediaminetetraacetic acid (HO₂CCH₂)₂NCH₂CH₂N(CH₂CO₂H)₂; 99%;    Alfa-Aesar;-   Ammonium hydroxide NH₄OH, 28-30%; Alfa-Aesar.-   Ge-ZSM-5 zeolite powder as prepared above was used for catalyst    preparation.

0.525 gram of ethylenediaminetetraacetic acid in 8 grams of D.I. waterwere heated up and 1 ml of ammonium hydroxide was added to dissolve theacid. 0.184 gram of ammonium hexachloroiridate(III) hydrate wasdissolved in this solution with stirring. After solution was cooled down19 ml of water was added. pH of solution was 9.70.

Solution was impregnated into 10 grams of Ge-ZSM-5 powder. Paste wasdried at 60° C. overnight with following calcination at 550° C. for 10hours.

Calcined powder was bound with silica at 50/50 wt. Material was calcinedat 550° C. for 6 hours. Sample was crushed and sized to 20/40 mesh.

Platinum was introduced by incipient wetness impregnation technique.Solution of tetraammineplatinum (II) nitrate in water was impregnatedinto the sample by portions in 3 steps with intermediate drying at 90°C. Catalyst was calcined at 300° C. for 5 hours.

XRF analysis results are: 0.12% Na; 43.61% Si; 0.37% Al; 2.81% Ge;0.26%; Ir; 0.36% Pt.

Example 2 Synthesis of Pt—Re/Ge-ZSM-5

Chemicals Used:

-   Ammonium perrhenate NH₄ReO₄; 99+%; Aldrich Chemicals;-   Tetraammineplatinum (II) nitrate (NH₂)₄Pt(NO₃)₂; Aldrich;-   Ethylenediaminetetraacetic acid (HO₂CCH₂)₂NCH₂CH₂N(CH₂CO₂H)₂; 99%;    Alfa-Aesar;-   Ammonium hydroxide NH₄OH, 28-30%; Alfa-Aesar.-   Ge-ZSM-5 zeolite powder as prepared above was used for catalyst    preparation.

0.525 grams of ethylenediaminetetraacetic acid in 8 grams of D.I. waterwere heated up and 1 ml of ammonium hydroxide was added to dissolve theacid. 0.100 gram of ammonium perrhenate was dissolved in this solutionwith stirring. After solution was cooled down 19 ml of water was added.pH of solution was 9.50. Solution was impregnated into 10 grams ofGe-ZSM-5 powder. Paste was dried at 60° C. overnight with followingcalcination at 600° C. for 10 hours.

Calcined powder was bound with silica at 50/50 wt. Material was calcinedat 550° C. for 6 hours. Sample was crushed and sized to 20/40 mesh.

Platinum was introduced by incipient wetness impregnation technique.Solution of tetraammineplatinum (II) nitrate in water was impregnatedinto the sample by portions in 3 steps with intermediate drying at 90°C. Catalyst was calcined at 300° C. for 5 hours.

XRF analysis results are: 0.12% Na; 43.76% Si; 0.37% Al; 2.84% Ge;0.11%; Re; 0.37% Pt.

Example 3 Synthesis of Pt—Pd/Ge-ZSM-5

Chemicals Used:

-   Palladium nitrate Pd(NO₃)₂; 99.999%; 10 wt. % in 10 wt. % nitric    acid; Aldrich;-   Tetraammineplatinum (II) nitrate (NH₂)₄Pt(NO₃)₂; Aldrich.

Ge-ZSM-5 powder was bound with silica at 50/50 wt. Material was calcinedat 550° C. for 6 hours. Sample was sized to 20/40 mesh. Bound zeolitewas ammonium ion-exchanged with 0.5M NH₄NO₃ solution at 60° C. threetimes.

Sample was calcined at 550° C. for 6 hours. Sample was ion-exchangedwith 0.002M Pd(NO₃)₂ solution at 60° C. in four steps in four days.Sample was washed several times with D.I. water, dried at 90° C. andcalcined at 300° C. for 5 hours.

Platinum was introduced into sample by ion-exchange procedure.Ion-exchange was made at 60° C. by using 0.005M (NH₂)₄Pt (NO₃)₂solution.

XRF analysis results are: 0.00% Na; 43.91% Si; 0.36% Al; 1.86% Ge; 0.22%Pd; 0.37% Pt.

Example 4 Synthesis of Pt—Ru/Ge-ZSM-5

Chemicals Used:

-   Ammonium aquopentachlororuthenate (III) (NH₄)₂[RuCl₅(H₂O)];    Alfa-Aesar;-   Tetraammineplatinum (II) nitrate (NH₂)₄Pt(NO₃)₂; Aldrich.

Ge-ZSM-5 powder was bound with silica at 50/50 wt. Material was calcinedat 550° C. for 6 hours. Sample was sized to 20/40 mesh.

Bound zeolite was ammonium ion-exchanged with 0.5M NH₄NO₃ solution at60° C. three times. Sample was calcined at 550° C. for 6 hours.

Sample was ion-exchanged with 0.002M (NH₄)₂[RuCl₅(H₂O)] solution at 80°C. for 17 hours. Sample was washed several times with D.I. water, driedat 60° C. and calcined at 300° C. for 5 hours.

Platinum was introduced into sample by ion-exchange procedure.Ion-exchange was made at 60° C. by using 0.005M (NH₂)₄Pt(NO₃)₂ solution.

XRF analysis results are: 0.01% Na; 43.58% Si; 0.36% Al; 2.11% Ge; 0.24%Ru; 0.34% Pt.

Example 5 Synthesis of Pt—Rh/Ge-ZSM-5

Chemicals Used:

-   Rhodium (III) chloride hydrate RhCl₃.xH₂O; 38-40% Rh; Aldrich;    Tetraammineplatinum (II) nitrate (NH₂)₄Pt(NO₃)₂; Aldrich.

Ge-ZSM-5 powder was bound with silica at 50/50 wt. Material was calcinedat 550° C. for 6 hours. Sample was sized to 20/40 mesh.

Bound zeolite was ammonium ion-exchanged with 0.5M NH₄NO₃ solution at60° C. three times. Sample was calcined at 550° C. for 6 hours.

Sample was ion-exchanged with 0.002M RhCl₃.xH₂O solution at 80° C. infour steps in four days. Sample was washed several times with D.I.water, dried at 90° C. and calcined at 300° C. for 5 hours.

Platinum was introduced into sample by ion-exchange procedure.Ion-exchange was made at 60° C. by using 0.005M (NH₂)₄Pt(NO₃)₂ solution.

XRF analysis results are: 0.00% Na; 43.61% Si; 0.36% Al; 1.82% Ge; 0.13%Rh; 0.35% Pt.

Example 6 Synthesis of Pt—Fe/Ge-ZSM-5

Chemicals Used:

-   Iron acetate Fe(MCO₂)₂; 99.995%; Aldrich;-   Tetraammineplatinum (II) nitrate (NH₂)₄Pt(NO₃)₂; Aldrich.

Ge-ZSM-5 powder was bound with silica at 50/50 wt. Material was calcinedat 550° C. for 6 hours. Sample was sized to 20/40 mesh.

Bound zeolite was ammonium ion-exchanged with 0.5M NH₄NO₃ solution at60° C. three times. Sample was calcined at 550° C. for 6 hours.

Sample was ion-exchanged with 0.028M Fe(MCO₂)₂ solution at RT withstirring for about 18 hours. Sample was washed several times with D.I.water, dried at 60° C. and calcined at 300° C. for 5 hours.

Platinum was introduced into sample by ion-exchange procedure.Ion-exchange was made at 60° C. by using 0.005M (NH₂)₄Pt(NO₃)₂ solution.

XRF analysis results are: 0.05% Na; 43.67% Si; 0.38% Al; 2.31% Ge; 0.47%Fe; 0.36% Pt.

Example 7 Syntheses of Pt—Co/Ge-ZSM-5 Synthesis A and Synthesis B

Chemicals Used:

-   Cobalt acetate Co(MCO₂)₂; 99.995%; Aldrich;-   Tetraammineplatinum (II) nitrate (NH₂)₄Pt(NO₃)₂; Aldrich.

Ge-ZSM-5 powder was bound with silica at 50/50 wt. Material was calcinedat 550° C. for 6 hours. Sample was sized to 20/40 mesh.

Bound zeolite was ammonium ion-exchanged with 0.5M NH₄NO₃ solution at60° C. three times. Sample was calcined at 550° C. for 6 hours.

Sample was ion-exchanged with 0.09M Co(MCO₂)₂ solution at 60° C. in twosteps, each for about 3-5 hours. Sample was washed several times withD.I. water, dried at 60° C. and calcined at 300° C. for 5 hours.

Platinum was introduced into sample by ion-exchange procedure.Ion-exchange was made at 60° C. by using 0.005M (NH₂)₄Pt (NO₃) 2solution.

XRF analysis results for Synthesis A: 0.03% Na; 43.93% Si; 0.37% Al;2.13% Ge; 0.31% Co; 0.41% Pt.

XRF analysis results for Synthesis B: 0.00% Na; 44.07% Si; 0.39% Al;2.13% Ge; 0.62% Co; 0.36% Pt.

Example 8 Pt—Sn/Ge-ZSM-5

Chemicals Used:

-   Tin (II) chloride dihydrate SnCl₂.2H₂O; 98%; Aldrich Chemicals;-   Tetraammineplatinum (II) nitrate (NH₂)₄Pt(NO₃)₂; Aldrich;-   Ethylenediaminetetraacetic acid (HO₂CCH₂)₂NCH₂CH₂N(CH₂CO₂H)₂; 99%;    Alfa-Aesar;-   Ammonium hydroxide NH₄OH, 28-30%; Alfa-Aesar.

Ge-ZSM-5 zeolite powder was used for catalyst preparation. 1.254 gramsof ethylenediaminetetraacetic acid in 2 grams of D.I. water were heatedup and 1 ml of ammonium hydroxide was added to dissolve the acid. 0.0855gram of tin chloride dehydrate was dissolved in this solution withstirring. After solution was cooled down 19 ml of water was added. pH ofsolution was 6.59. Solution was impregnated into 10 grams of Ge-ZSM-5powder. Paste was dried at 60° C. overnight with following calcinationat 550° C. for 10 hours.

Calcined powder was bound with silica at 50/50 wt. Material was calcinedat 550° C. for 6 hours. Sample was crushed and sized to 20/40 mesh.

Platinum was introduced by incipient wetness impregnation technique.Solution of tetraammineplatinum (II) nitrate in water was impregnatedinto the sample by portions in 3 steps with intermediate drying at 90°C. Catalyst was calcined at 300° C. for 5 hours.

XRF analysis results are: 0.13% Na; 43.48% Si; 0.36% Al; 2.84% Ge;0.22%; Sn; 0.36% Pt.

All catalysts were reduced in a flowing hydrogen/nitrogen (50/50 byvolume) mixture at 400° C. Some catalysts as indicated were pretreatedwith 1 vol % hydrogen sulfide in a nitrogen gas stream until sulfidebreakthrough achieved and then swept with hydrogen/nitrogen (50/50 byvolume) at 400° C. for approximately one hour to remove excess sulfur.All catalysts were tested in a stainless steel tube at 500° C. using 34cc/min of propane at 22 psig total pressure. The products were analyzedby on-line sampling to a gas chromatograph where all hydrocarboncomponents with carbon numbers between 1 and 10 were quantitativelydetermined. Results for yield [fraction of BTX (benzene, toluene,xylenes) in product] and conversion (portion of propane converted) areshown in the graphs below.

Numerous modifications and variations of the present invention arepossible in light of the above teachings. It is to be understood that,within the scope of the appended claims, the invention may be practicedother than as specifically described.

What is claimed as new and desired to be secured by letter of patent ofthe United States of America is:
 1. A catalyst for conversion ofhydrocarbons comprising: a) a germanium zeolite; and b) platinum and ametal selected from Group 7, Group 8, Group 9, and Group 10, depositedon the germanium zeolite.
 2. The catalyst of claim 1 wherein the metalis rhenium, ruthenium, rhodium, iridium, palladium, cobalt, and/or iron.3. The catalyst of claim 1 wherein the zeolite is MFI.
 4. The catalystof claim 2 wherein the other metal is rhenium, rhodium, iridium, and/orpalladium.
 5. The catalyst of claim 3 wherein the zeolite is ZSM-5.
 6. Aprocess for synthesizing a germanium zeolite catalyst comprising: a)preparing a germanium zeolite; b) depositing platinum and a metalselected from Group 7, Group 8, Group 9, Group 10 or tin on thegermanium zeolite; and c) calcining the germanium zeolite, saidcalcining occurring after preparation of the zeolite, before depositingplatinum and the metal on the germanium zeolite or before or afterdepositing platinum and the metal on the germanium zeolite.
 7. Theprocess of claim 6 wherein the metal is rhenium, ruthenium, rhodium,iridium, palladium, cobalt, and/or iron.
 8. The process of claim 6wherein the zeolite is MFI.
 9. The process of claim 8 wherein thezeolite is ZSM-5.
 10. A process for the conversion of hydrocarbonscomprising: a) contacting a hydrocarbon stream containing alkanes,olefins or mixtures thereof having 2 to 12 carbon atoms per moleculewith a germanium zeolite catalyst comprising platinum and a metalselected from Group 7, Group 8, Group 9 or Group 10 deposited on thegermanium zeolite; and b) recovering the product.
 11. The process ofclaim 10 wherein the other metal is rhenium, ruthenium, rhodium,iridium, palladium, cobalt, and/or iron.
 12. The process of claim 10wherein the zeolite is MFI.
 13. The process of claim 10 wherein alkanesor olefins are straight, branched, cyclic, or mixtures thereof.
 14. Theprocess of claim 10 wherein the zeolite is ZSM-5.